The present invention relates generally to an improved suspension damper for a motor vehicle. More specifically, the present invention relates to a suspension damper capable of adjusting the height of the motor vehicle.
Suspension dampers are typically attached to a spring assembly of a vehicle suspension system to dampen vibrations derived from such variables as rough road surfaces, pot holes, and unbalanced tires. The spring force generally determines the height of the vehicle and the damper controls the dynamic vehicle motion. Often, it is desirable to supplement the spring force to maintain a controlled vehicle height at different levels of vehicle load. One method of doing so is to affix a height leveling damper to the suspension system that adjusts the height of the vehicle relative to the load on the vehicle.
Presently, to maintain the controlled vehicle height, the spring force is supplemented with an air leveling damper that requires an external compressor and controller. An air sleeve is attached to the outside of the air leveling damper to supply an extending force to the damper for maintaining the controlled vehicle height. This type of damper adds a significant amount of mass to the vehicle due to the addition of the compressor and the controller. Further, the controller associated with the air leveling damper requires sensors and related electronics to adjust the height of the vehicle.
Therefore, it would be desirable to utilize a self leveling damper with the vehicle suspension system that does not require additional external components such as an air compressor and a controller.
The present invention is a suspension damper assembly capable of adjusting the height of an automobile. A cylinder tube defining a pumping chamber is aligned concentrically within a reservoir tube. A fluid reservoir is formed between the reservoir tube and the cylinder tube. A piston has a plunger slideably disposed within the cylinder tube. The plunger is affixed to a piston shaft inserted through a first end of the reservoir tube. The shaft is inserted through a shaft guide that seals the pumping chamber from the fluid reservoir at the first end.
A gas cup is slideably disposed within the assembly forming a fluid chamber within the cylinder tube with the shaft guide. The gas cup also forms a gas chamber with a second end of the cylinder tube. The gas cup includes a cup conduit connecting the pumping chamber to the reservoir chamber. When the gas cup pumps fluid into the pumping chamber, fluid pressure inside the pumping chamber is increased providing a force that telescopes the shaft outwardly of the cylinder tube thereby raising the height of the vehicle.
The shaft is inserted through a spring that biases the plunger away from the shaft guide retracting the shaft into the cylinder tube. The shaft guide includes a shaft conduit connecting the fluid chamber to the reservoir. The shaft conduit is sealed with a shaft valve wherein compression of the spring opens the shaft valve allowing fluid to pass from the pumping chamber to the reservoir chamber thereby reducing the outward force of the piston and lowering the height of the vehicle.
The suspension damper of the present invention adjusts the height of the vehicle using mechanisms completely concealed within the damper. The damping action of the piston transfers fluid throughout the damper to adjust the height of the vehicle according to the load on the vehicle. Unlike height adjusting dampers presently available, external compressor or electronic controllers are not required.